Psoriatic Arthritis Causes

The cause of psoriatic arthritis (PsA) is unknown. Experts believe some people may be predisposed to an autoimmune disease like psoriatic arthritis. In fact, studies show a stronger genetic or family link to this particular disease than other autoimmune rheumatic diseases. About 40 percent of people who are diagnosed with psoriatic arthritis and psoriasis have family members affected by the disease.

Not everyone who has psoriasis develops psoriatic arthritis. Psoriasis is not infectious, but the disease might be triggered by a strep throat. In addition to infections, researchers believe PsA also can be triggered by extreme stress or an injury that makes the immune system go into overdrive in people who are genetically more likely to get the disease.